The present invention relates to a jack capable of changing the position a switch upon the fitting or removing of a plug into or from the jack.
There are well known jacks of this type in which a movable contact strip is housed in a box-shaped jack case with its one end fixed to the jack case while its other free end is positioned facing the plug fitting opening of jack case, a slide switch is attached onto the lower face of jack case in such a way that the operating lever of slide switch is inserted into the jack case through the lower face thereof, and when the free end of movable contact strip is urged to the side way by the plug fitted into the plug fitting opening of jack case, the operating lever of slide switch is pressed by the urged free end of movable contact strip to thereby change over the slide switch. However, these jacks each including the jack case mounted on the slide switch become too bulky to thereby make it difficult to be incorporated into slim electronic appliances such as micro-cassette tape recorder and small-sized radio. In addition, it has been requested these days that jacks employed in slim electronic appliances be ultra-small-sized together with plugs fitted into jacks. When jacks are ultra-small-sized like this to meet such need, the displaced amount of movable contact strip pressed and displaced by the plug becomes extremely small. Therefore, in the case of conventional jacks in which the free end of movable contact strip is pressed as described above by the plug and the operating lever of slide switch is further pressed by the pressed free end of movable contact strip, the changeover of slide switch is liable to become incomplete.
There are also well known jacks of this type in which the different changeover switch is incorporated integral into the jack case. However, the number of changeover circuits for changeover switches incorporated has a limit and even if a plurality of changeover switches are incorporated into the jack case, the jack case itself becomes bulky causing a problem in being incorporated into appliances. In addition, in the case where all of changeover circuits are not necessarily used responding to the purpose of use, the user must use the jack larger than necessity requests.
On the other hand, the jack maker must make various kinds of jack such as having no changeover switch and having changeover switches which are different in the number of changeover circuits to meet needs of user.